The Curious Case of the “Release” Button bug in Defender for Office Quarantine
Last Updated on March 20, 2026 by Michael Morten Sonne Introduction Hi all, the #BugHunter here again! 👋… The post The Curious Case of the “R...
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March 2026 Update for Office 365 for IT Pros
We've released monthly update #129 for the Office 365 for IT Pros eBook. Current subscribers can download the EPUB and PDF files from gumroad.com. ...
Read Article →Securing Microsoft Business Premium Part 06: Securing Email with Defender for Office 365
Sharing is caring — While that is a mantra I follow myself, collaboration needs to be done securely. Email is often the first and most widely used ...
Read Article →January 2026 Update for Office 365 for IT Pros
Monthly Update #127 for the Office 365 for IT Pros eBook (2026 edition) is now available for current subscribers to download from Gumroad.com. In t...
Read Article →Microsoft Increases Office 365 and Microsoft 365 License Prices
Customers will see their bills increase from July 1, 2026, when Microsoft 365 pricing increases go into effect, adding up to $3/month for licenses....
Read Article →Office 365 for IT Pros December 2025 Update
The Office 3675 for IT Pros team is happy to announce that the files for update #126 are available for subscribers to download from Gumroad.com. Th...
Read Article →How to Check if Shared Mailboxes Need MDO Licenses
Shared mailboxes might need Microsoft Defender for Office 365 licenses, but how do you identify how many licenses? We use PowerShell to do the job ...
Read Article →Office 365 for IT Pros November 2025 Update
The Office 365 for IT Pros Team is happy to announce the availability of the November 2025 update. Subscribers can download the PDF and EPUB files ...
Read Article →Microsoft Issues Updated Guidance for Defender for Office 365 Licensing
Some inconsistencies in the MDO P2 service description and licensing terms exposed a need for tenants to license every user and shared mailboxes. M...
Read Article →Configuring Conditional Access for Guest Users: Allowing Only Office 365 and Essential Apps
Introduction Configuring Conditional Access (CA) for guest users can be challenging when you want to strictly limit access to Office 365 and a few ...
Read Article →Office 365 for IT Pros October 2025 Update
Monthly update #124 for the Office 365 for IT Pros (2026 edition) eBook is now available. Current subscribers can download the updated PDF and EPUB...
Read Article →September 2025 Update for Office 365 for IT Pros
Monthly update #123 is available for the Office 365 for IT Pros eBook. Subscribers can download updated EPUB and PDF files for the main book and th...
Read Article →Microsoft Defender for Office 365, Shared Mailboxes, and Microsoft 365 Groups
Microsoft Defender for Office 365 (MDO) requires shared mailboxes to be licensed but doesn't extend the same requirement to Microsoft 365 Groups. G...
Read Article →Unexpected Microsoft Defender for Office 365 License Requirement for Shared Mailboxes
A question about shared mailboxes brought up the topic of licensing requirements when a tenant has Microsoft Defender for Office 365 (MDO). The new...
Read Article →Monthly Update #122 Available for Office 365 for IT Pros eBook
Monthly update #122 is now available for the Office 365 for IT Pros eBook. Subscribers can download PDF and EPUB files for the update from Gumroad....
Read Article →Defender for Office 365 Auto-Remediation of Malicious Messages (AIR)
In Defender for Office Automated Investigation and Response (AIR) is important. Microsoft has improved the features surrounding Auto-Remediation of...
Read Article →Announcing Office 365 for IT Pros (2026 Edition)
Office 365 for IT Pros (2026 edition), the 12th in an eBook series going back to May 2015, is now available. Covering all the essential aspects of ...
Read Article →Launch Plan for Office 365 for IT Pros (2026 Edition)
We're a week away from the launch of the Office 365 for IT Pros (2026 edition) eBook, the 12th edition issued since the first book appeared in 2015...
Read Article →Using a Copilot Agent in SharePoint to Interact with Office 365 for IT Pros
Copilot Studio Agents can use files as knowledge sources to reason over when they respond to user prompts. We explain how to use the monthly PDFs i...
Read Article →June 2025 Update Available for Office 365 for IT Pros (2025 Edition)
Monthly update #120 (June 2025) is available for the Office 365 for IT Pros eBook. This is the last update for the 2025 edition as the 2026 edition...
Read Article →Defender for Office 365: Visualisation of the Tenant Allow/Block List features
During my work with customers, when I explain the tenant allow and block features in Microsoft Defender for Office 365 P1/P2, I often get the quest...
Read Article →May 2025 Update for the Office 365 for IT Pros eBook
Subscribers for Office 365 for IT Pros (2025 edition) eBook can download the May 2025 updates (#119) now. Update #11.3 for the PowerShell book is a...
Read Article →Microsoft Defender for Office 365 Exposes Bad Links in Email Preview
Microsoft Defender for Office 365 includes many tools to help investigators manage threat. The Email Preview tool shows the layout and appearance o...
Read Article →Office 365 for IT Pros April 2025 Update
The April 2025 Update for the Office 365 for IT Pros eBook is now available for subscribers to download. This is monthly update #118 for Office 365...
Read Article →Office 365 for IT Pros March 2025 Update
The Office 365 for IT Pros writing team is thrilled to announce that monthly update #117 for March 2025 is now available for subscribers to downloa...
Read Article →Tracking Down Bootleg Copies of Office 365 for IT Pros
Free downloads of Office 365 for IT Pros, normally in PDF format, are available from sites around the internet. All are illegal and outdated copies...
Read Article →Monthly Update #116 for Office 365 for IT Pros
Monthly update #116 (February 2025) is available for the Office 365 for IT Pros eBook. The refresh includes update #8 new files for the Automating ...
Read Article →All About the Office 365 for IT Pros GitHub Repository
The Office365ITPros GitHub repository holds over 300 PowerShell scripts showing how to interact with Microsoft 365 and Entra ID. Anyone can contrib...
Read Article →Office 365 for IT Pros January 2025 Update
Monthly update #115 is now available for download by subscribers to the Office 365 for IT Pros (2025 edition) eBook. The files available to subscri...
Read Article →Office 365 for IT Pros December 2024 Update
The Office 365 for IT Pros writing team is thrilled to announce the availability of the December 2024 update (monthly update #114). Current subscri...
Read Article →Office 365 for IT Pros November 2024 Update
Monthly Update #113 (November 2024) for the Office 365 for IT Pros eBook is now available for download by current subscribers from Gumroad.com. An ...
Read Article →Office 365 for IT Pros October 2024 Update
The Office 365 for IT Pros team is delighted to announce the availability of monthly update #112. Subscribers for the 2025 edition can now download...
Read Article →Office 365 for IT Pros September 2024 Update
Files are available to download for the September 2024 update for the Office 365 for IT Pros (2025 edition) eBook. This is monthly update #111 for ...
Read Article →Office 365 for IT Pros August 2024 Update
The first update for Office 365 for IT Pros (2025 edition) or monthly update #110 is now available for subscribers to download. The update covers b...
Read Article →Office 365 for IT Pros 2025 Edition is Now Available
Office 365 for IT Pros 2025 edition, the 11th edition of the most comprehensive and in-depth book covering the Microsoft 365 Office servers, is now...
Read Article →The End for Office 365 Connectors Comes Into Sight
Office 365 Connectors bring data from external sources into Microsoft 365 apps like Teams and Outlook. Workflows and Power Automate are replacing C...
Read Article →Office 365 for IT Pros June 2024 Update
The June 2024 update for the Office 365 for IT Pros 2024 edition ebook is available for download. We're also announcing the availability of the 202...
Read Article →Office 365 for IT Pros May 2024 Update Available
Another month, another update for the Office 365 for IT Pros eBook. In this case, it's monthly update #107 for Office 365 for IT Pros (2024 edition...
Read Article →Protecting Against QR Code Phishing in Defender for Office 365
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Read Article →Defender for Office 365 – Hunting and responding to QR code-based phishing attacks
Last Updated on April 3, 2024 by Michael Morten Sonne Intoduction Now you can strengthening your defense against… The post Defender for Offic...
Read Article →Office 365 for IT Pros April 2024 Update
The April 2024 update for the Office 365 for IT Pros eBook is now available for subscribers to download from Gumroad.com or Amazon.com. Like every ...
Read Article →Office 365 for IT Pros March 2024 Update
The Office 365 for IT Pros eBook team has released the March 2024 update for the only eBook covering the Microsoft 365 ecosystem that's updated mon...
Read Article →Office 365 for IT Pros eBook Team Welcomes Michel de Rooij
The Office 365 for IT Pros team welcomes Michel de Rooij as a new author. As a PowerShell Pro, he'll like the code to update the impersonation prot...
Read Article →Office 365 for IT Pros February 2024 Update
The February 2024 update for the Office 365 for IT Pros eBook (monthly update #104) is now available for download. Lots happened during January in ...
Read Article →Microsoft Cloud Revenues Powered by Office 365
Office 365 Reaches 400 million. Well, to be precise, in their FY24 Q2 results, Microsoft said that the figure is "over 400 million paid seats," but...
Read Article →How to protect Microsoft Teams with Microsoft 365 Defender
Microsoft released in the past months additional protections for Microsoft Teams. The new Office protection is part of the Defender for Office prod...
Read Article →Office 365 for IT Pros January 2024 Update
The January 2024 update for the Office 365 for IT Pros eBook is available for subscribers to download from Gumroad.com or Amazon. Like any monthly ...
Read Article →Exchange Online Protection & Defender for Office 365 – Common Microsoft 365 Security Mistakes Series
Exchange Online Protection (EOP) and Microsoft Defender for Office 365 (MDO) are the email and collaboration security services native to Microsoft ...
Read Article →December 2023 Update for Office 365 for IT Pros eBook is Available
The December 2023 update (monthly update #102) for the Office 365 for IT Pros eBook is now available for subscribers to download. While Microsoft h...
Read Article →How to disable Automapping for a shared mailbox in Outlook for Office 365?
Last Updated on March 14, 2024 by Michael Morten Sonne If you are like me, you probably use… The post How to disable Automapping for a shared...
Read Article →The Microsoft Defender for Office 365 Recommended Configuration Analyzer (ORCA)
Last Updated on March 14, 2024 by Michael Morten Sonne Introduction ORCA is a report that you can… The post The Microsoft Defender for Office...
Read Article →How to set up Evilginx to phish Office 365 credentials
Check out this article via web browser: How to set up Evilginx to phish Office 365 credentials Update: Evilginx 3 is here! This post is based on Ev...
Read Article →Deploying Office 365 with Intune as a Win32 App (and Why You’d Want To)
Office 365, or Microsoft 365 Apps for Enterprise, or whatever it’s called this month, can be deployed by Intune to Windows 10 devices using a...
Read Article →Microsoft Defender for Office 365: Check protection policies with Configuration Analyzer
Microsoft Defender for Office 365 is one of the three types of Advanced Threat Protection that Microsoft offers. With Microsoft Defender for Office...
Read Article →Enabling Plus Addressing in Office 365 Exchange Online
In December 2019 Microsoft included support for Plus Addressing in their roadmap (ID 59441) for Office 365. In the meantime this feature is release...
Read Article →The Difference Between Cloud App Security Discovery (CAD), Office 365 Cloud App Security (OCAS), and Microsoft Cloud App Security (MCAS)
Microsoft Cloud App Security (MCAS), Redmond’s cloud app security broker (CASB) offering, is a powerful tool for investigating and pro-active...
Read Article →Office 365 Templated policies and Preset security policies in Exchange Online Protection and Office 365 ATP
In my deep dive article on Office 365 Advanced Threat Protection (ATP) I mentioned that Microsoft provides best practices as described in the follo...
Read Article →Office 365 Advanced Threat Protection (ATP) deep dive
Around 5 years ago (April 2015) Microsoft announced Exchange Online Advanced Threat Protection (ATP), which was renamed to Office 365 Advanced Thre...
Read Article →Prerequisites and Planning for Centrally Deploying Office 365 Outlook Add-Ins
Deploying Outlook add-ins (“apps”) for your O365 tenant is an intuitive experience via AppSource. As a Global Administrator, click GET ...
Read Article →Did you already enable DKIM and DMARC for your Office 365 domains?
When you host your email on the Exchange Online (EXO) platform part of Office365 you can implement several security measures to make sure that emai...
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